Research on Surface Charge Dissipation Characteristics of Epoxy Resin Insulation Materials Under Different Aging Conditions

Epoxy resin is a commonly used insulating material in gas-insulated metal-enclosed switchgear (GIS), recognized for its commendable insulation, mechanical, thermal, and adhesive characteristics. The insulators of GIS circuit breakers experience varying degrees of deterioration due to different load, overvoltages, and environmental factors, which significantly affect the equipment replacement cycles. Currently, it is challenging to achieve non-destructive determination of the aging degree of epoxy resin insulators. This paper proposes a method for evaluating the insulation degradation by measuring the surface charge dissipation rate. Experiments were conducted using a four-axis motorized rotation platform for epoxy resin specimens under different thermal aging conditions. Surface charge dissipation tests were carried out after pre-charging, investigating the surface charge dissipation before and after aging. Combining SEM and FTIR tests on specimens, the results indicate that thermally aged epoxy resin specimens experience more severe degradation, with a significant increase in surface charge dissipation rate.